This application relates generally to gas turbine engines and, more particularly, to methods and apparatus for removing particulate matter from gas turbine engine combustors.
Combustors are used to ignite fuel and air mixtures in gas turbine engines. Known combustors include at least one dome attached to a combustor liner that defines a combustion zone. Fuel injectors are attached to the combustor in flow communication with the dome and supply fuel to the combustion zone. Fuel enters the combustor through a dome assembly attached to a spectacle or dome plate.
The dome assembly includes an air swirler secured to the dome plate, and radially inward from a flare cone. The flare cone is divergent and extends radially outward from the air swirler to facilitate mixing the air and fuel, and spreading the mixture radially outwardly into the combustion zone. A divergent deflector extends circumferentially around the flare cone and radially outward from the flare cone. The deflector prevents hot combustion gases produced within the combustion zone from impinging upon the dome plate. At least some known deflectors include integrally formed cooling passages which direct air towards the flare cone to facilitate impingement backside cooling of the flare cone.
During operation, particulate matter ingested into the engine may undesirably accumulate in the impingement passages and block the flow of cooling air through the passages. Over time, continued operation with blocked cooling air passages may cause premature failure of the flare cone. To facilitate preventing overheating of the flare cone, known combustors are periodically inspected and washed to remove any particulate matter that may have built up. Known wash systems spray water, or a mixture of water and detergent, from a spray nozzle downstream into the combustor to remove accumulated particulate matter from the combustor. Such water washing systems restore some of the losses, but because the impingement cooling passages are not visibly accessible for inspection, and as such, the water washes may not adequately remove the particulate matter from the impingement cooling passages. Additionally, because of the orientation of the deflector-flare cone assembly, particulate matter dislodged upstream from the passages may become forcibly lodged in the passages as the cleaning solution is channeled downstream through the combustor.